Schools in poor neighborhoods overwhelmingly received the worst grades under Texas' new rating system -- but even typically high-performing districts got C’s and D’s, according to scores that will be released Friday.

The “what if” grades show how schools and districts could fare in the new A-F system, which won’t take effect until 2018.

The plan to give public schools letter grades has infuriated educators across the state. As of Thursday, 152 districts have adopted resolutions opposing it. Critics say the approach is over-simplistic and stigmatizes poor schools.

All North Texas districts meet current state standards according to results released this summer. But 11 would have earned an F in at least one of four categories in the new grading system, including Mesquite, Wylie, Farmersville, Lancaster and Cedar Hill. Highland Park, Plano, Allen and McKinney each got at least one C.

“That’s amazing when you consider that they all met the standard two weeks ago and the scores, the data, haven’t changed,” Mesquite Superintendent David Vroonland said. Both the new and old system are largely based on the same STAAR results and other data.

Dallas ISD got a D in student performance and B's in three other categories.

DeSoto got an F in student performance and in preparing kids for life after high school.

“We continue to wait for more information from TEA on the methodology of the new system, however, this continued attack on public schools, your DeSoto public schools, is an attack on the foundation of our country,” superintendent David Harris said in a prepared statement on Thursday.

“The government ‘ranking’ and comparing schools, feeds the agenda of those claiming our schools are failing and vouchers are the answer. Meanwhile, public schools tend to be underfunded and over mandated by the state and federal governments.”

Hear Eva-Marie Ayala discuss the A-F grades on the Texas Standard radio show.

The Legislature approved the grading system during the 2015 session. Other states, including Oklahoma and West Virginia, have similar accountability measures. But Virginia killed its plan to give letter grades over concerns of fairness to schools.

The Texas Education Agency is releasing grades in four areas: how well students performed on state tests; how much progress students made from year to year on those tests, how well schools are closing the gaps between poor children and their peers; and students’ college or career readiness. Next year, a fifth measure will allow schools to grade themselves on student and community engagement. Schools and districts will also receive an overall grade.

Critics of the system say it doesn’t actually reflect what’s going on in classrooms and will only stigmatize schools in poor neighborhoods that will have a harder time meeting standards. Those schools already struggle to recruit and keep talented teachers and engaged families.

In North Texas, school districts with a large share of poor students were much more likely to receive D’s or F’s for student achievement. The districts that got A’s in that category had more affluent student bodies.

But many high-performing districts got low marks for how well they are closing achievement gaps and in postsecondary readiness.

Sunnyvale, for example, earned A’s in student performance and progress but an F in closing those gaps. Sixteen percent of the district’s students are considered economically disadvantaged, up from 10 percent two years ago.

Such students tend to struggle more on tests. As more of those children moved into the district, they not only had to pass the STAAR tests but had to achieve at higher levels to match their peers in order for the gaps to close.

Sunnyvale superintendent Doug Williams joined other critics who are concerned that the new grading system will fuel momentum for vouchers and other school choice options.

“The timing of the release is the issue - right before the legislative session,” Williams said.

Highland Park earned a C for postsecondary readiness and Wylie earned an F. Meanwhile, the Dallas school district bested them both with a B. That area gives districts credit for students who complete certain career tech courses, earn college credit, complete certain advanced courses or do well on college entrance exams like the SAT or ACT.

Wylie superintendent David Vinson said that district’s low grade was caused by a coding error related to career tech courses. “This is one of the reasons educators are concerned about this system, when a coding issues can cause a potential A or B to become an F,” he said Thursday night.

Highland Park spokesman Jon Dahlander that while the grades are provisional, they show the state needs to continue work on the system.

The school district had an average ACT score of 27.6, a full seven points higher than the state’s average, and an average composite score of 1833 on the SATs, far outpacing Texas’ average of 1393. About 90 percent of Highland Park graduates enroll in college.

“This obviously shows the flaw in grading schools and districts with a single letter grade,” Dahlander said.

While many of Dallas ISD’s most struggling schools earned low grades as expected, some progress was noted. The district as a whole earned a B for student progress.

Still, the results were disappointing to Superintendent Michael Hinojosa, who also has issues with the grading system.

“As a district, we’ve focused our efforts on having a lot of growth, and maybe -- when we're talking about the district as a whole -- the overall scores are an indication of the progress that we're making. But when you drill down to the different schools, things don't make a lot of sense to me."

Hinojosa pointed to grades of two widely disparate campuses: Dade Middle School and Woodrow Wilson High School.

Dade, a chronically low-performing campus, has made strides according to the state's old rating system and DISD's own metrics. Despite recently being rated in the top tier of DISD's own rating system, Dade received two F’s, a C and a D from the state.

Woodrow received C’s across the board though it’s considered DISD's top traditional high school.

"I think this is just going to create more confusion for everyone -- the board members, parents, the community," Hinojosa said. "But that's what's going to happen when you try to give a simple solution to a complex issue."

When discussing the new system last month, Morath -- a former Dallas ISD board member -- agreed that boiling schools down to a simple letter grade is difficult. But he said the end result will be an accountability standard that gives schools credit for progress while being more transparent to communities.

“You have to have something that’s fairly easy for folks to understand and concentrate on improvement over time,” Morath said.